When connecting a connection terminal of a semiconductor chip with a circuit pattern on a connection substrate, a paste-like or film-shape anisotropic conductive adhesive is often used. In this case, there is a need to improve the adhesive force of the anisotropic conductive adhesive with a passivation film on the surface on the connecting side of the semiconductor chip, and to improve the adhesion between the anisotropic conductive adhesive and the semiconductor chip, between the anisotropic conductive adhesive and an organic substrate, and between a wiring metal surface of a wiring circuit and the anisotropic conductive adhesive.
To achieve this, an ordinary silane coupling agent, which has an organic reactive group, such as vinyltrimethoxysilane and epoxytrimethoxysilane, and a trialkoxy group, and has a relatively low boiling point, is added to the anisotropic conductive adhesive. However, when a semiconductor chip is mounted on a wiring substrate via an anisotropic conductive adhesive containing such an ordinary silane coupling agent, the adhesion with the passivation film cannot be said to be sufficient. As a result, problems arise such as peeling occurring on the adhesion interface due to a heat shock from a solder reflow treatment or the like, and voids being produced in the cured adhesive due to vaporization of the silane coupling agent.
Therefore, it has been proposed to use a silane coupling agent which has an imidazole residue in the molecule instead of the conventional ordinary silane coupling agent (Patent Document 1).
[Patent Document 1] Japanese Patent Application Laid-Open No. Hei 9-12683